AO1

• Hemispheric lateralisation - idea that the brain is divided into two hemispheres, each with different functions.
• Split-brain research was used to investigate hemispheric lateralisation.
• Sperry - all participants had their corpus callosum between two hemispheres cut in order to separate the two hemispheres and control frequent and severe epileptic seizures.
• Main communucation line was removed (corpus callosum)
• Findings for: describing what you see, recognition by touch, composite words and matching faces.
• Describe what you see

  When a picture of an object was shown to a patient's right visual field, they could easily describe what was seen. However, if the same object was shown to the left visual field the patient could not describe what was seen and typically reported there was nothing there.
• Describing what you see

  Inability to describe objects in left visual field was because of the lack of language centers in the right hemisphere.
• Recognition by touch

  Although patients could not attach verbal labels to objects projected in the left visual field, they were able to select a matching object from a grab-bag of different objects using their left hand.
• Composite words

  If two words were presented simultaneously, one on either side of the visual field, the patient would write with their left hand the word on the left and say the word on the right. The superiority of the right hemisphere in terms of drawing tasks was also evident.
• Matching faces

  Right hemisphere also dominant in terms of recognising faces: when asked to match a face from a series of other faces, the picture processed by the right hemisphere (left visual field) was constantly selected, while the picture presented to the left hemisphere was ignored.
• Matching faces

  When a composite picture made up of two different halves of a face was presented, one half to each hemisphere, the left hemisphere dominated in terms of verbal description whereas the right hemisphere dominated in terms of selecting a matching picture.